Cycas beddomei is an endemic and critically endangered tropical dry deciduous dioecious shrub confined to India. It reproduces through sexual mode only. C. sphaerica is a data deficient red-listed species. It is a tropical dry deciduous dioecious shrub confined to northern Eastern Ghats of India. It reproduces asexually and sexually. Both the species are anemophilous. The restricted participation of plants in annual coning event, restricted seed dispersal, seed infestation and other factors relating to natural regeneration contribute to the endemic and endangered status of the plants.

In Decalepis hamiltonii, extended flowering pattern, self-incompatibility, pollinator limitation, absence of seed dormancy, abortion of a considerable percentage of seedlings prior to establishment are contributing factors for the regulation of its population size. Further, the roots of this plant are over-exploited due to its commercial value in the preparation of a soft drink "nannari sharbat" in India. In Shorea tumbuggaia, non-annual flowering, massive flowering, short flowering period, partial flowering at tree level, seed predation, absence of seed dormancy and inability of seedlings to...